The Effect of Onion Juice and pH on a Cow Eye. Jenna and Maggie. The purpose of this lab is to observe how the tissues in a cow’s eye are affected by the amount and acidity of sulfuric acid and onion juice. The method used to isolate the product was serial dilution. The serial diultion of concentrated sulfuric acid was done to produce pH leves of 4.0, 5.0, 5.5, and 6.0. Different concentration amounts of sulfuric acid were placed on the cow eyes. The main data that was collected from the lab was the actual level of acidity within the sulfuric acid. Also the main qualitative data was recorded once the eyeballs had sulfuric acid on them and were observed underneath a dissection microscope. The initial pH, tested on the eye, of 4.0 caused the most noticeable effects on the eye; the pupil of the eye got darker and the sclera turned red. The last pH concentration of 6.0, caused minimal effects since the eye seemed to be absorbing the acid. . It was hard to get very descriptive pictures of the eye, because the eye was rotten and was absorbing the acid. From the data it can be concluded that there was a student made error when creating the dilated solutions.
Key Words:
acidity, sulfuric acid, concentration, dissection microscope, serial dilution, and pH
Photos of Apparatus and Results: Figure 1: Result of eye after acid was placed on it Figure 2: Apparatus of the eye
Two Journal Citations:
1. Burnham, P.M. (n.d.). Propanethial s-oxide. Retrieved from //http://www.chm.bris.ac.uk/motm/pso/psoc.htm// This website gave a clear understanding of what propanethial s-oxide is and how it is created from an onion. This gave us background information of the oxide and helped the students understand what exactly it is. It also explains why eyes, water and also how the s-oxide mixes with the water and makes sulfuric acid. The last paragraph of this source is not relavent to our project because it explains how one could wear goggles to avoid crying when cutting an onion.
2. Tear Production. http://www.stlukeseye.com/anatomy/TearProduction.html (Accessed 2011 January 6) The process of crying is much more complicated than many think.Initially, tears are produced by the stimulation of two glands, lacrimalglands, which are placed above the eyes. When eyes begin to tear, lacrimal fluid, also known as tears, are released. However, the brain sends an initial message to the body for a need for tears and the lacrimal glands secret the fluid. Excess tears are supposed to collect in an area known as the lacrimal lake. However, when the lacrimal duct is blocked, tears continue to pour down ones cheek. Furthermore, tears continue to drain into the nasal or throat passages.
Abstract:
Key Words:
acidity, sulfuric acid, concentration, dissection microscope, serial dilution, and pH
Graph:
Photos of Apparatus and Results:
Two Journal Citations:
1. Burnham, P.M. (n.d.). Propanethial s-oxide. Retrieved from //http://www.chm.bris.ac.uk/motm/pso/psoc.htm//
This website gave a clear understanding of what propanethial s-oxide is and how it is created from an onion. This gave us background information of the oxide and helped the students understand what exactly it is. It also explains why eyes, water and also how the s-oxide mixes with the water and makes sulfuric acid. The last paragraph of this source is not relavent to our project because it explains how one could wear goggles to avoid crying when cutting an onion.
2. Tear Production. http://www.stlukeseye.com/anatomy/TearProduction.html (Accessed 2011 January 6)
The process of crying is much more complicated than many think.Initially, tears are produced by the stimulation of two glands, lacrimalglands, which are placed above the eyes. When eyes begin to tear, lacrimal fluid, also known as tears, are released. However, the brain sends an initial message to the body for a need for tears and the lacrimal glands secret the fluid. Excess tears are supposed to collect in an area known as the lacrimal lake. However, when the lacrimal duct is blocked, tears continue to pour down ones cheek. Furthermore, tears continue to drain into the nasal or throat
passages.